App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 167 · 40 questions

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

1. 1.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 pop() takes off the last item. What does this code show?
   let songs = ["Kites", "Sunrise", "Rain", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Sunrise (d) Rain
3. 3.💾 What number does this code show?
   let points = 5;
   points = points - 2;
   points = points + 4;
   show(points);
4. 4.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Science", "Maths", "Art", "Sports"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Maths (c) Music (d) Science
5. 5.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Sports", "Hindi", "Music"];
   show(notes[2]); (a) Music (b) Hindi (c) Sports (d) Maths
6. 6.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a shared to-do list (d) your last game level
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Hindi", "Music", "Maths", "Science"];
   show(notes[0]); (a) Hindi (b) Music (c) Art (d) Maths
8. 8.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 pop() takes off the last item. What does this code show?
   let friends = ["Kabir", "Aman", "Zoya"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Zoya (b) Kabir (c) Aman
10. 10.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
11. 11.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
12. 12.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
13. 13.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 What number does this code show?
    let score = 4;
    score = score - 3;
    score = score + 1;
    show(score);
15. 15.💾 What number does this code show?
    let lives = 5;
    lives = lives - 5;
    lives = lives + 4;
    show(lives);
16. 16.💾 What number does this code show?
    let notes = ["Art", "Maths", "Science"];
    notes.push("Hindi");
    notes.push("Music");
    show(notes.length);
17. 17.True or false: your last game level fits saving in the cloud. (a) False (b) True
18. 18.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) your last game level (d) a class leaderboard
19. 19.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
20. 20.💾 What number does this code show?
    let lives = 9;
    lives = lives - 2;
    lives = lives + 5;
    show(lives);
21. 21.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Meera", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Zoya (c) Meera
22. 22.💾 What is a variable? (a) a named box for a value (b) a picture (c) a phone setting (d) a type of screen
23. 23.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) chat messages to friends (d) notes to read offline
24. 24.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Kabir", "Riya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Meera (c) Aman (d) Kabir
25. 25.Which of these fits saving on the phone? (a) a class leaderboard (b) a draft you are typing (c) photos on two devices (d) a shared to-do list
26. 26.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Sports", "Hindi"];
    show(notes[2]); (a) Hindi (b) Sports (c) Maths
30. 30.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
31. 31.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 0 (c) 2 (d) 1
32. 32.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the screen turns off (c) you send a message (d) the app is closed
34. 34.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) chat messages to friends (d) a draft you are typing
35. 35.💾 What number does this code show?
    let notes = ["Art", "Music", "Science"];
    notes.push("Sports");
    notes.push("Hindi");
    show(notes.length);
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Rain", "Sunrise", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Monsoon (c) Stars (d) Sunrise
37. 37.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Art"];
    show(notes[1]); (a) Art (b) Science (c) Maths
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Arjun", "Riya"];
    show(friends[1]); (a) Arjun (b) Riya (c) Meera
40. 40.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a cloud leaderboard (d) a shared chat

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